- Although second-generation antipsychotic medications have fewer serious side effects and complications than first-generation ones, they are strongly associated with weight gain for reasons that are as yet unknown. Comparing the effects of second-generation antipsychotics with a high weight-gain liability (HWGL) low weight-gain liability (LWGL) antipsychotics may provide more information on which medications are best suited for different individuals. Researchers are interested in studying how people taking various antipsychotics compare with controls in regard to food craving and eating behavior. This knowledge should help to guide practitioners when advising patients about the weight-gain effects of these medications.